The gaga greenies of Europe are about to charge you for flying here in America.

In a stunning slap at the sovereignty of everyone on the other six continents, the European Court of Justice last week said it was just fine and dandy for the European Union to levy fees on planes flying elsewhere.

As the Europeans see it, global warming is so bad that they have to tax … us.

Here’s how it works: You take off from London for Los Angeles; your flight route runs north-northwest over Scotland and out of European air space pronto. You pay a tax for this, which, while annoying, isn’t much different than a highway toll.

But as your flight continues on — clipping south of the North Pole, then swooping over the Canadian Arctic Archipelago and Alberta and into the United States and LAX — the EU will tax you for each one of those miles, too.

Starting next year, the EU will tote up all the miles a plane flies to or from any European city, factor in the fuel usage and charge a “carbon levy” for all emissions that are more than 85 percent of 2002 levels. No airline is going to eat that cost, so you’ll get the bill, perhaps listed as an “environmental surcharge.”

Like most taxes, it starts out small, maybe $20 or so (no one really knows yet) — and then the fine folks in Brussels will start jacking up the price. By 2020, it could be $60 — the sky’s the limit.

And the EU’s not just planning to hike the tax — it’s already mandated it. By 2020, it will tax planes for using more than half their 2002 fuel, and while newer planes are more fuel efficient, they’re not making gains close to that level.

According to Fitch, United, Continental, Delta and American are likely to get hit the most, because about 20 percent of their revenue comes from European travel.

Things could get pretty ugly. China is already making noise about pulling its order for 10 double-decker A-380s from Europe’s Airbus (probably pretty good news for Boeing). Other countries may jack up landing fees or inflict similar taxes on foreign carriers.

Until now, Europe and the United Kingdom have been content to go it alone with their silly climate taxes, smugly thinking (along with Chevrolet Volt drivers) that they are somehow saving the world. No more.

All of this seems downright silly. Here in America, the last (overwhelmingly Democratic) Congress refused to pass an anti-warming bill that would’ve ordered the country to cut carbon-dioxide emissions an impossible 83 percent by 2050.

The bill actually passed the House, with President Obama’s support. But Obama’s public approval plummeted, while Republican poll ratings jumped, so the Senate punted the business of impoverishing us over to the president and his Environmental Protection Agency.

One reason that the bill was so unpopular was that it demonstrably did nothing about climate change — even if Europe, Australia, Canada and other industrialized nations adopted the same policy. That’s because the massive emissions from China, India and other developing nations will dwarf ours.

In 2009, the last year for which we have good data, China emitted 142 percent of the US total of “greenhouse gases” — up from just 51 percent 10 years earlier.

But the Europeans aren’t willing to let futility stop them from launching a perfectly disastrous crusade — or even from exporting it to America.

Patrick J. Michaels is senior fellow in environmental studies at the Cato Institute and the author of “Climate Coup: Global Warming’s Invasion of Our Government and Our Lives.”